The former Nationals leader has apologised for describing an Indigenous voice to Parliament as a "third chamber".
Nationals MP Barnaby Joyce has admitted he may have been wrong to call a proposal for an Indigenous voice to Parliament a "third chamber".
The former Nationals leader apologised "unreservedly" for the "mistake" under questioning from the ABC's Patricia Karvelas on Thursday.
“If I got it wrong, I apologise. I apologise. There you go. Unreservedly,” he said.
“What I do say, we’ve got – we’ve got to take this debate forward … take the debate forward in a form that succeeds. There’s no point going to a referendum with something that is not going to work.”
Mr Joyce's apology follows Indigenous Australians Minister Ken Wyatt's commitment last week to hold a referendum on Indigenous constitutional recognition within three years.
The announcement prompted a backlash from conservative MPs, forcing Prime Minister Scott Morrison to clarify that his opposition to enshrining an Indigenous voice in the constitution remained.
Others in the Coalition remain unapologetic about using the term "third chamber".
Senior minister Peter Dutton indicated last week the government would pursue symbolic-only recognition in the constitution.
"We're not in favour of a third chamber or a separate voice," Mr Dutton told the Nine Network on Friday.
The idea was a key proposal endorsed by more than 250 Aboriginal and Torres Strait Islander people in the landmark 2017 Uluru Statement from the Heart.
Advocates for an Indigenous voice have repeatedly rejected the characterisation of the proposed representative body as a "third chamber", arguing it is about ensuring they have a say on decisions affecting their communities.
Mr Wyatt has described the voice to parliament as "problematic".
"We've got to separate the voice, and we've got to separate constitutional recognition," Mr Wyatt told ABC radio last week.
"If the voice fails in any referendum, and if we were to put it up and it was not going to be accepted, then it is folly. We cannot do that."